Boiler furnace heat extraction system

Abstract

The application provides a boiler furnace heat extraction system, which comprises a first storage device for storing cold-state heat storage medium; an in-furnace heat absorption device arranged in the interior of a boiler furnace and connected with the first storage device; a second storage device for receiving and storing hot-state heat storage medium formed after heat absorption of the in-furnace heat absorption device; an out-furnace heat exchange device arranged in the exterior of the boiler furnace and used for heat exchange with the hot-state heat storage medium; and a conveying device connected between the heat exchange discharge end and the first storage device and used for conveying the cold-state heat storage medium formed after heat exchange back to the first storage device, wherein the cold-state / hot-state heat storage medium is solid heat storage particles; and the first storage device, the in-furnace heat absorption device, the second storage device and the out-furnace heat exchange device are sequentially arranged from high to low along the gravity direction. The application can extract high-temperature waste heat in the interior of the boiler furnace, saves energy conversion, increases the energy storage scale through cyclic heat storage and release, and improves the peak shaving capacity and operation flexibility of the boiler unit.

Description

Technical Field

[0001] This invention relates to the field of energy storage and heat exchange technology, specifically to a boiler furnace heat extraction system. Background Technology

[0002] Currently, the installed capacity of renewable energy sources such as wind power and photovoltaics is growing rapidly, but their intermittency and volatility pose challenges to the stable operation of the power grid, requiring the grid to flexibly adjust resources for peak shaving and valley filling. Coal-fired power, as the main power source with large installed capacity and stable power generation, bears the heavy responsibility of peak shaving. However, traditional coal-fired power units are prone to unstable combustion, deteriorated heat exchange, and decreased economic efficiency under low-load operating conditions, making it difficult to meet the actual needs of deep peak shaving. Therefore, the flexible transformation of traditional coal-fired power units using coal-fired power generation coupled with energy storage technology has become an effective way to improve system flexibility.

[0003] Among various energy storage methods, thermal energy storage has the advantages of large storage capacity and low cost. Currently, the heat transfer process of conventional boilers mainly relies on the high-temperature flame and flue gas in the furnace to directly transfer heat to the water-cooled walls through thermal radiation. However, existing boiler units suffer from insufficient operational flexibility and low thermal efficiency. Summary of the Invention

[0004] This invention provides a boiler furnace heat extraction system, which aims to solve the technical problems of insufficient operational flexibility and low overall thermal efficiency of boiler units in the prior art.

[0005] This invention provides a boiler furnace heat extraction system, comprising: The first storage device is configured to store the cold heat storage medium to be absorbed. The furnace heat absorption device is installed inside the boiler furnace and has a heat absorption feed end and a heat absorption discharge end. The heat absorption feed end is connected to the first storage device to allow the cold heat storage medium to circulate and absorb the heat inside the boiler furnace. The second storage device is connected to the heat absorption discharge end and is configured to receive and store the hot heat storage medium formed after the heat absorption device in the furnace absorbs heat. The external heat exchange device is located outside the boiler furnace and has a heat exchange feed end, a heat exchange discharge end, and a heat exchange medium channel inside. The heat exchange feed end is connected to the second storage device to receive the hot heat storage medium and exchange heat with the heat exchange medium entering the heat exchange medium channel. A conveying device is connected between the heat exchange discharge end and the first storage device, and is configured to convey the cold heat storage medium formed after heat exchange back to the first storage device. The cold heat storage medium and the hot heat storage medium are solid heat storage particles. The first storage device, the furnace heat absorption device, the second storage device and the furnace heat exchange device are arranged in sequence from high to low along the direction of gravity.

[0006] According to the above technical solution, the cold thermal storage medium flows from the first storage device into the furnace heat absorption device inside the boiler furnace. By absorbing heat from the high-temperature flue gas, it is converted into a hot thermal storage medium, enabling direct extraction and utilization of high-temperature waste heat from inside the boiler furnace. This eliminates unnecessary energy conversion steps and effectively improves the overall thermal efficiency of the system. Simultaneously, the hot thermal storage medium is temporarily stored in the second storage device and enters the external heat exchange device during the heat release phase to transfer heat with the heat exchange medium. The cold thermal storage medium, having completed heat release, is transported back to the first storage device by a conveying device to achieve circulation. This circulating heat storage and release structure effectively increases the energy storage capacity and enhances the peak-shaving capability and operational flexibility of traditional boiler units in response to load fluctuations.

[0007] Furthermore, by employing solid thermal storage particles as both cold and hot thermal storage media, these particles offer advantages such as a high upper limit of operating temperature, good heat resistance, high energy density, low material cost, and good circulation, ensuring the stability and economy of the high-temperature heat extraction process within the boiler furnace. Simultaneously, the top-down arrangement of each device allows the thermal storage medium to fall smoothly under gravity and flow sequentially through each device, reducing energy consumption during transportation.

[0008] Optionally, the location of the in-furnace heat absorption device inside the boiler furnace is determined according to the temperature field distribution inside the boiler furnace and is matched with the heat storage temperature zone of the cold heat storage medium.

[0009] According to the above technical solution, the furnace heat absorption device is arranged based on the actual temperature field distribution inside the boiler furnace, so that the temperature of the heat extraction environment matches the heat storage temperature zone of the heat storage medium. This can maintain the efficient heat storage and avoid increasing the high temperature resistance requirements and material costs of the furnace heat absorption device due to excessively high local temperatures.

[0010] Optionally, the first storage device is provided with a first inlet and a first outlet, and the first storage device is connected to the heat absorption inlet of the furnace heat absorption device through the first outlet; the second storage device is provided with a second inlet and a second outlet, and the second storage device is connected to the heat absorption outlet of the furnace heat absorption device through the second inlet and to the heat exchange inlet of the furnace heat exchange device through the second outlet; the inlet side of the conveying device is connected to the heat exchange outlet of the furnace heat exchange device, and the outlet side of the conveying device is connected to the first inlet of the first storage device.

[0011] Optionally, it further includes: a first feed valve, disposed at the first feed inlet of the first storage device, for regulating the feed flow rate of the cold thermal storage medium; a first discharge valve, disposed at the first discharge outlet of the first storage device, for regulating the discharge flow rate of the cold thermal storage medium; a second feed valve, disposed at the second feed inlet of the second storage device, for regulating the feed flow rate of the hot thermal storage medium; and a second discharge valve, disposed at the second discharge outlet of the second storage device, for regulating the discharge flow rate of the hot thermal storage medium; the first feed valve, the first discharge valve, the second feed valve, and the second discharge valve all have a heat insulation layer or a cooling protection structure.

[0012] According to the above technical solution, the valves distributed at each inlet and outlet can control the flow rate of the cold and hot heat storage media, thereby achieving dynamic adjustment of the overall heat absorption and release power. Simultaneously, the insulation layer or cooling protection structure configured on each valve can correspondingly extend its service life.

[0013] Optionally, it also includes: a purging and cooling assembly, at least connected to the interior of the furnace heat absorption device, configured to purge and cool the furnace heat absorption device by introducing airflow when the furnace heat absorption device stops working.

[0014] According to the above technical solution, the purging and cooling assembly can purge and cool the inside of the furnace heat absorption device by introducing airflow when the heat absorption device in the furnace is in a stopped state. This can reduce the risk of blockage and effectively prevent high-temperature creep failure caused by dry burning of the pipeline of the heat absorption device in the high-temperature furnace.

[0015] Optionally, the in-furnace heat absorption device includes straight tubes, serpentine tubes, coils, or multiple parallel tube bundles; The materials used for the furnace heat absorption device include high-temperature resistant alloy tubes, ceramic-lined metal tubes, or composite wear-resistant tubes.

[0016] According to the above technical solution, by utilizing serpentine tubes or coils, the movement path and heating time of solid heat storage particles inside the pipe can be extended, enhancing the airflow disturbance of the external high-temperature flue gas and strengthening the heat exchange effect between the high-temperature flue gas outside the pipe and the heat storage medium inside the pipe. Simultaneously, the use of high-temperature resistant alloy tubes or ceramic-lined metal tubes ensures that the furnace heat absorption device possesses excellent oxidation resistance and wear resistance.

[0017] Optionally, the external heat exchange device is a fluidized bed heat exchanger, which includes at least a main chamber, a wind chamber located at the bottom of the main chamber, an air distribution plate located at the top of the wind chamber, and a heat exchange medium channel located above the air distribution plate. The wind chamber is configured to receive fluidizing gas, which passes upward through the air distribution plate to fluidize the hot heat storage medium and exchange heat with the heat exchange medium flowing in the heat exchange medium channel. The heat exchange medium includes air, water, or supercritical carbon dioxide.

[0018] According to the above technical solution, efficient and uniform heat exchange can be achieved through a fluidized bed heat exchanger.

[0019] Optionally, both the first and second storage devices are conical-bottom silos with insulation jackets; the second storage device is detachably connected between the heat absorption device inside the furnace and the heat exchange device outside the furnace.

[0020] According to the above technical solution, the conical-bottom silo structure can effectively vent the internal heat storage medium; at the same time, the insulation layer can effectively reduce heat loss during storage. In addition, the detachable connection structure of the second storage device facilitates its movement and loading onto transport vehicles, improving the flexibility of cross-regional thermal energy dispatch.

[0021] Optionally, the solid thermal storage particles are sensible thermal storage particles or thermochemical thermal storage particles; sensible thermal storage particles include natural sand, quartz sand, alumina, or ceramics; thermochemical thermal storage particles include non-redox thermochemical particles or redox thermochemical particles, wherein redox thermochemical particles are metal oxides that can generate oxygen-rich gas when absorbing heat; non-redox thermochemical particles include calcium carbonate; redox thermochemical particles include manganese oxide or copper oxide.

[0022] Optionally, it also includes: a gas-solid separation device, disposed between the heat absorption discharge end of the heat absorption device in the furnace and the second storage device, having a gas outlet; a combustion-supporting guide pipe, disposed between the gas outlet of the gas-solid separation device and the boiler furnace; the thermochemical heat storage particles are oxidation-reduction thermochemical particles; the gas-solid separation device is configured to separate the oxygen-enriched gas generated when the thermochemical heat storage particles absorb heat from the solid thermochemical heat storage particles, and the combustion-supporting guide pipe is configured to introduce the separated oxygen-enriched gas into the boiler furnace to assist the boiler furnace in oxygen-enriched combustion.

[0023] According to the above technical solution, for the working condition of using redox thermochemical particles, after the solid heat storage particles absorb heat and decompose, the oxygen-rich gas released is recovered by the gas-solid separation device and reinjected into the boiler furnace through the combustion-supporting guide pipe for combustion support. This can significantly improve the combustion efficiency of the fuel and further enhance the overall economy of the boiler unit. Attached Figure Description

[0024] Figure 1 A schematic diagram of the overall structure of a boiler furnace heat extraction system according to an embodiment of the present invention; Figure 2 A schematic diagram illustrating the coordination of heat exchange in the external heat exchange device according to an embodiment of the present invention; Figure 3 A top view of the external heat exchange device in an embodiment of the present invention; Figure 4 A schematic diagram of a serpentine tube as the furnace heat absorption device in an embodiment of the present invention; Figure 5 A schematic diagram of a coil as the furnace heat absorption device in an embodiment of the present invention.

[0025] Reference numerals in the attached drawings: Boiler furnace heat extraction system 100, first material storage device 10, first feed inlet 11, first discharge outlet 12, first feed valve 13, first discharge valve 14, furnace heat absorption device 20, second material storage device 30, second feed inlet 31, second discharge outlet 32, second feed valve 33, second discharge valve 34, furnace external heat exchange device 40, heat exchange feed end 41, heat exchange discharge end 42, heat exchange working medium channel 43, main chamber 44, wind chamber 45, air distribution plate 46, baffle plate 47, conveying device 50, fan 61, turbulent air intake device 62, boiler 200. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] refer to Figure 1 The boiler furnace heat extraction system 100 in this embodiment includes a first material storage device 10, an in-furnace heat absorption device 20, a second material storage device 30, an external heat exchange device 40, and a conveying device 50.

[0028] The first storage device 10 is configured to store the cold thermal storage medium to be absorbed. Specifically, the first storage device 10 is used to store the cold thermal storage medium that is at room temperature or a lower temperature after releasing heat. When heat extraction from the furnace is required, the first storage device 10 releases the cold thermal storage medium stored inside.

[0029] The in-furnace heat absorption device 20 is installed inside the furnace of the boiler 200, and has a heat absorption feed end and a heat absorption discharge end. The heat absorption feed end is connected to the first storage device 10 to allow the cold heat storage medium to circulate and absorb heat from inside the furnace of the boiler 200. Specifically, the in-furnace heat absorption device 20 is arranged inside the furnace of the boiler 200. The cold heat storage medium flowing through the in-furnace heat absorption device 20 can exchange heat with the high-temperature flue gas inside the furnace of the boiler 200 through the tube wall of the in-furnace heat absorption device 20, so that the cold heat storage medium is heated and transformed into a hot heat storage medium. This heat extraction process is completed directly inside the boiler 200, and the absorbed heat can be stored in the hot heat storage medium in the form of sensible heat or chemical heat.

[0030] The second storage device 30 is connected to the heat absorption discharge end and is configured to receive and store the hot heat storage medium formed after the heat absorption device 20 in the furnace absorbs heat. Specifically, the second storage device 30 receives and stores the hot heat storage medium flowing out from the furnace of the boiler 200, thereby enabling flexible adjustment of heat release according to the actual external heat demand.

[0031] refer to Figure 1 and Figure 2 The external heat exchange device 40 is located outside the furnace of the boiler 200 and has a heat exchange feed end 41, a heat exchange discharge end 42, and an internal heat exchange medium channel 43. The heat exchange feed end 41 is connected to the second storage device 30 to receive the hot heat storage medium and exchange heat with the heat exchange medium entering the heat exchange medium channel 43. Specifically, when heat needs to be released, the hot heat storage medium flows out from the second storage device 30 and enters the internal heat exchange device 40 through the heat exchange feed end 41, where it exchanges heat with the heat exchange medium entering the heat exchange medium channel 43, releasing the high-temperature heat energy stored in the hot heat storage medium. The heated heat exchange medium is then drawn out and can be used for various applications such as industrial park heating, direct access to the superheater or reheater of a steam turbine unit for power generation, and heating during peak electricity consumption periods to improve the peak capacity of the boiler unit.

[0032] refer to Figure 1 and Figure 2 The conveying device 50 connects the heat exchange outlet 42 and the first storage device 10, and is configured to transport the cold thermal storage medium formed after heat exchange back to the first storage device 10. Specifically, the medium that has completed heat release in the external heat exchange device 40 is cooled down again and transformed into a cold thermal storage medium, and then enters the conveying device 50. The conveying device 50 can transport the cold thermal storage medium back to the first storage device 10, thereby completing the cycle. The returned cold thermal storage medium can be stored in the first storage device 10, waiting for the next heat extraction from the furnace of the boiler 200.

[0033] Through the coordination of the first storage device 10, the in-furnace heat absorption device 20, the second storage device 30, the external heat exchange device 40, and the conveying device 50, the cold-state heat storage medium flows from the first storage device 10 into the in-furnace heat absorption device 20 inside the boiler 200 furnace. By absorbing heat from the high-temperature flue gas, it is converted into a hot-state heat storage medium, directly extracting and utilizing the high-temperature waste heat inside the boiler 200 furnace. This eliminates unnecessary energy conversion steps and effectively improves the overall thermal efficiency of the system. Simultaneously, the hot-state heat storage medium is temporarily stored in the second storage device 30 and enters the external heat exchange device 40 during the heat release phase to transfer heat with the heat exchange medium. The cold-state heat storage medium, having completed heat release, is transported back to the first storage device 10 by the conveying device 50 to achieve circulation. This cyclical heat storage and release architecture effectively increases the energy storage capacity and enhances the deep peak-shaving capability and operational flexibility of traditional boiler units in response to load fluctuations.

[0034] In this embodiment, both the cold and hot thermal storage media are solid thermal storage particles. Specifically, using solid thermal storage particles as the heat extraction and transfer medium offers advantages such as a high upper limit of operating temperature, good heat resistance, high energy density, low material cost, and good recyclability. This makes them suitable for direct application in high-temperature operating scenarios where heat is extracted directly from the furnace of a boiler, thus ensuring the stability and economy of the system during high-temperature operation.

[0035] refer to Figure 1 In this embodiment, the first material storage device 10, the furnace heat absorption device 20, the second material storage device 30, and the furnace heat exchange device 40 are arranged sequentially from high to low along the direction of gravity.

[0036] The first storage device 10 is provided with a first inlet 11 and a first outlet 12. The first storage device 10 is connected to the heat-absorbing inlet end of the furnace heat-absorbing device 20 through the first outlet 12.

[0037] refer to Figure 1 and Figure 2 The second storage device 30 is provided with a second inlet 31 and a second outlet 32. The second storage device 30 is connected to the heat absorption outlet end of the furnace heat absorption device 20 through the second inlet 31, and is connected to the heat exchange inlet end 41 of the furnace heat exchange device 40 through the second outlet 32.

[0038] refer to Figure 1 and Figure 2 The feeding side of the conveying device 50 is connected to the heat exchange discharge end 42 of the furnace heat exchange device 40, and the discharge side of the conveying device 50 is connected to the first feeding port 11 of the first storage device 10.

[0039] Specifically, the first storage device 10, the in-furnace heat absorption device 20, the second storage device 30, the external heat exchange device 40, and the conveying device 50 are interconnected to form a flow loop for the heat storage medium. The first storage device 10, the in-furnace heat absorption device 20, the second storage device 30, and the external heat exchange device 40 are arranged in a top-to-bottom configuration along the height direction, allowing the heat storage medium to be naturally driven by its own gravitational potential energy, flowing smoothly through the connected pipes and corresponding devices by gravity, thereby reducing the additional energy consumption generated by powering the heat storage medium. Simultaneously, the heat exchange inlet 41 and the heat exchange outlet 42 of the external heat exchange device 40 are also set at a height difference, allowing the heat storage medium input at the higher heat exchange inlet 41 to flow to the lower heat exchange outlet 42 and enter the conveying device 50 accordingly.

[0040] In the circulation path of the heat storage medium, the first storage device 10, located at a higher position, releases the low-temperature cold heat storage medium (such as low-temperature solid heat storage particles) through its first discharge port 12 to the heat absorption feed end of the furnace heat absorption device 20 by gravity. After the cold heat storage medium (such as low-temperature solid heat storage particles) flows inside the furnace of the boiler 200 and completes heat absorption and heating, it flows directly from the heat absorption discharge end into the second feed port 31 of the second storage device 30 below by gravity for temporary storage. When heat release is required, the hot heat storage medium (such as high-temperature solid heat storage particles) continues to flow out from the second discharge port 32 of the second storage device 30 by gravity and directly enters the heat exchange feed end 41 of the furnace heat exchange device 40, thereby exchanging heat with the internal heat exchange working medium.

[0041] The conveying device 50 can be a rail-mounted crane, bucket elevator, or other type of lifting device, capable of lifting and conveying the heat storage medium to the first storage device 10, and the conveying device 50 itself has temperature resistance. After the hot heat storage medium (such as high-temperature solid heat storage particles) completes heat release and cooling in the external heat exchange device 40, it enters the feed side of the conveying device 50 from the heat exchange outlet 42. The conveying device 50 provides upward mechanical conveying power to overcome gravity, lift the cold heat storage medium (such as low-temperature solid heat storage particles) that has completed heat release, and transport it back to the first feed inlet 11 of the first storage device 10 located at a higher position, thereby realizing the circulation of the heat storage medium.

[0042] In this embodiment, the location of the furnace heat absorption device 20 inside the furnace of the boiler 200 is determined according to the temperature field distribution inside the furnace of the boiler 200 and is matched with the heat storage temperature zone of the cold heat storage medium.

[0043] Specifically, the boiler 200 may be in the form of a pulverized coal boiler, a fluidized bed boiler, a gas-fired boiler, etc. The specific arrangement of the in-furnace heat absorption device 20 in the furnace of the boiler 200 depends on the actual temperature field inside the furnace.

[0044] As an example, for pulverized coal boilers, the flue gas temperature in the furnace is relatively high, reaching 1200℃. Under such high temperature conditions, the requirements for the high-temperature resistance of the pipes transporting the cold heat storage medium inside the furnace are high, such as the resistance to oxidation, the resistance to high-temperature creep, and the wear resistance. Not only is the material cost high, but it is also easy to be damaged. Therefore, it is possible to arrange the furnace heat absorption device 20 in a relatively low temperature part, such as arranging the furnace heat absorption device 20 in the combustion zone area or the upper screen superheater area.

[0045] As another example, for fluidized bed boilers, the temperature of the dilute phase zone is relatively moderate, generally between 750℃ and 950℃. This temperature zone is consistent with the heat storage temperature zone of many cold heat storage media. Therefore, heat can be extracted directly by arranging the in-furnace heat absorption device 20 in the dilute phase zone of the boiler 200 furnace.

[0046] By arranging the furnace heat absorption device 20 based on the actual temperature field distribution inside the furnace of boiler 200, the heat extraction environment temperature can be matched with the heat storage temperature zone of the cold heat storage medium. This not only maintains the efficient operation of heat storage, but also avoids increasing the high temperature resistance requirements of the pipes and the material cost due to excessively high local temperatures.

[0047] In some embodiments, the in-furnace heat absorption device 20 can be arranged in multiple pipelines within the corresponding heat extraction area of ​​the boiler 200 furnace, distributed accordingly in the furnace space. During heat extraction, the outer wall of the in-furnace heat absorption device 20 directly contacts the high-temperature flue gas inside the boiler 200 and performs convective heat exchange. Simultaneously, it fully absorbs the radiant heat released by the high-temperature flue gas and efficiently transfers the heat to the internally filled or flowing heat storage medium through the pipe wall, thereby achieving the absorption and storage of thermal energy. During this process, by dynamically adjusting the flow rate or velocity of the heat storage medium inside the in-furnace heat absorption device 20, the total heat extracted by the heat storage medium from inside the boiler 200 can be changed accordingly, thereby achieving flexible adjustment of the boiler 200's heat extraction power and the unit's peak-shaving capacity.

[0048] refer to Figure 1 The boiler furnace heat extraction system 100 in this embodiment also includes a first feed valve 13, a first discharge valve 14, a second feed valve 33, and a second discharge valve 34.

[0049] The first feed valve 13 is located at the first feed inlet 11 of the first storage device 10 and is used to regulate the feed flow rate of the cold thermal storage medium. The first discharge valve 14 is located at the first discharge outlet 12 of the first storage device 10 and is used to regulate the discharge flow rate of the cold thermal storage medium. Specifically, the first feed valve 13 is located at the first feed inlet 11 of the first storage device 10 and is used to control the flow rate of the cold thermal storage medium returned by the conveying device 50 into the first storage device 10. The first discharge valve 14 is located at the first discharge outlet 12 of the first storage device 10. When furnace heat extraction is required, the first discharge valve 14 is opened to allow the cold thermal storage medium to flow out of the first storage device 10. At this time, the discharge flow rate of the cold thermal storage medium can be controlled by controlling the opening degree of the first discharge valve 14. In practical applications, the first discharge valve 14 can be in the form of a star-shaped feed valve, a rotary feed valve, an electric gate valve, or a high-temperature resistant airlock valve.

[0050] Furthermore, by dynamically adjusting the opening of the first discharge valve 14 to change the flow rate of the cold thermal storage medium, the amount of heat extracted by the cold thermal storage medium from the furnace of the boiler 200 can be directly adjusted and changed. This allows the boiler unit to flexibly control the heat extraction power according to the actual load demand of the power grid while maintaining its own combustion stability, thereby effectively improving the boiler unit's deep peak-shaving capability in response to load fluctuations.

[0051] The second feed valve 33 is located at the second feed port 31 of the second storage device 30 and is used to regulate the feed flow rate of the hot storage medium. The second discharge valve 34 is located at the second discharge port 32 of the second storage device 30 and is used to regulate the discharge flow rate of the hot storage medium.

[0052] Specifically, the second feed valve 33 is located at the second feed inlet 31 of the second storage device 30, and is used to control the flow rate of the hot heat storage medium that has completed heat absorption into the second storage device 30. The second discharge valve 34 is located at the second discharge outlet 32 ​​of the second storage device 30. When heat needs to be released, the second discharge valve 34 is opened, allowing the hot heat storage medium to flow out of the second storage device 30 and into the subsequent external heat exchange device 40. Similarly, the discharge flow rate of the hot heat storage medium participating in heat release can also be controlled by adjusting the second discharge valve 34. In practical applications, the second discharge valve 34 can be a valve with high-temperature resistance, such as an electric gate valve, a slide gate valve, or a high-temperature resistant discharge valve.

[0053] In this embodiment, the first feed valve 13, the first discharge valve 14, the second feed valve 33, and the second discharge valve 34 all have a heat insulation layer or a cooling protection structure. Specifically, since the above-mentioned valves need to frequently come into contact with the heat storage medium during system operation, the first feed valve 13, the first discharge valve 14, the second feed valve 33, and the second discharge valve 34 are all equipped with a heat insulation layer or a cooling protection structure, which can resist the influence of high temperature environment on the internal mechanical structure of the valve, prevent the valve components from deforming or jamming due to heat, thereby extending the service life of the components and ensuring the reliability of flow control.

[0054] In this embodiment, a purging and cooling assembly is also included, which is at least connected to the interior of the furnace heat absorption device 20 and is configured to purge and cool the furnace heat absorption device 20 by introducing airflow when the furnace heat absorption device 20 stops working.

[0055] Specifically, refer to Figure 1 The purging and cooling assembly can be configured as a separate fan 61, located outside the boiler 200 and connected to the inside of the furnace heat absorption device 20, for blowing in airflow.

[0056] Further, refer to Figure 1 The purging and cooling assembly may include a fan 61 (such as a low-frequency fan), a turbulent suction device 62, and a compressed air pipeline. The fan 61 is connected to the furnace heat absorption device 20 and is located downstream of the first discharge valve 14, used to blow in airflow. The turbulent suction device 62 is connected to the furnace heat absorption device 20 and is located upstream of the second feed valve 33, used to draw out airflow, generating negative pressure to suck in residual heat storage medium (such as solid heat storage particles) inside the furnace heat absorption device 20. The compressed air pipeline is... Figure 1 The section between the blower 61 and the boiler 200, represented by a straight line or a broken line, is used to transmit airflow.

[0057] When the furnace heat absorption device 20 is in a stopped state, i.e., when the heat storage medium is no longer transported, the blower 61 and the turbulent suction device 62 are started. The blower 61 introduces airflow through the configured compressed air pipeline and draws it out through the turbulent suction device 62, thereby more effectively purging and unblocking the furnace heat absorption device 20 and cooling it down. Airflow purging reduces the possibility of internal heat storage medium deposition and blockage; it also prevents the risk of overheating caused by dry burning of the furnace heat absorption device 20 in the high-temperature furnace chamber, and reduces the risk of pipeline failure due to high-temperature creep caused by long-term high-temperature heating of the furnace heat absorption device 20.

[0058] In some embodiments, a wall temperature measuring thermocouple can be arranged at the bottom of the furnace heat absorption device 20 to monitor the tube wall temperature of the furnace heat absorption device 20 in real time. When the furnace heat absorption device 20 is in a shutdown state and the tube wall temperature of the furnace heat absorption device 20 is detected to be higher than the preset safety temperature, the purging cooling component is activated in time to introduce airflow for cooling and temperature reduction, thereby achieving safety protection for the furnace heat absorption device 20.

[0059] In some implementations, the purging and cooling assembly can also be connected to various pipelines transporting the thermal storage medium. Specifically, when the system is shut down or requires cleaning and maintenance, the purging and cooling assembly can introduce airflow into other pipelines used to transport the thermal storage medium for purging and unblocking, preventing the thermal storage medium from stagnating and becoming blocked at various transport stages.

[0060] Understandably, in this embodiment, the use of a fan 61, a turbulent suction device 62, and a compressed air pipeline to form a purging and cooling assembly is only a specific preferred embodiment. In practical applications, the specific structure of the purging and cooling assembly is not limited to this. Any airflow generator or guide device that can introduce airflow into the furnace heat absorber 20 to achieve purging, unblocking, and cooling functions when the furnace heat absorber 20 is in a stopped state can be used as a purging and cooling assembly.

[0061] In this embodiment, the furnace heat absorption device 20 includes a straight tube, a serpentine tube, a coil, or multiple parallel tube bundles. Specifically, the furnace heat absorption device 20 may be structurally composed of one or more combinations of straight tubes, serpentine tubes, coils, or multiple parallel tube bundles.

[0062] Further, refer to Figure 4 and Figure 5 The furnace heat absorption device 20 can preferably be a serpentine tube or a coil. By making the furnace heat absorption device 20 into a serpentine tube or a coil, the heating section distance of the heat storage medium inside the pipe can be increased, thereby extending the heating time of the heat storage medium inside the pipe and ensuring that the heat storage medium is fully heated. At the same time, the arrangement of the serpentine tube or coil allows the flue gas inside the boiler 200 to fully contact the outer wall of the furnace heat absorption device 20, enhancing the airflow disturbance of the flue gas outside the pipe, thereby enhancing the overall heat exchange effect.

[0063] Furthermore, since the heat storage medium in this embodiment is solid heat storage particles, during the transportation process, the solid heat storage particles can move in the furnace heat absorption device 20 in the form of particle flow or gas-solid two-phase flow, thus flowing smoothly.

[0064] Furthermore, the material of the furnace heat absorption device 20 includes high-temperature alloy tubes, ceramic-lined metal tubes, or composite wear-resistant tubes. Specifically, since the furnace of the boiler 200 typically has high flue gas temperatures and is subject to harsh conditions such as fly ash scouring, the furnace heat absorption device 20 is made of high-temperature alloy tubes, ceramic-lined metal tubes, or composite wear-resistant tubes. This enables the furnace heat absorption device 20 to have good resistance to high-temperature oxidation and wear resistance, effectively coping with the effects of high temperatures and fly ash scouring within the furnace, thereby improving operational stability.

[0065] refer to Figure 2 and Figure 3 In this embodiment, the external heat exchange device 40 is a fluidized bed heat exchanger. The fluidized bed heat exchanger includes at least a main chamber 44, a wind chamber 45 located at the bottom of the main chamber 44, a wind distribution plate 46 located at the top of the wind chamber 45, and a heat exchange medium channel 43 located above the wind distribution plate 46. The wind chamber 45 is configured to receive fluidizing gas. The fluidizing gas passes upward through the wind distribution plate 46 to fluidize the hot heat storage medium and exchange heat with the heat exchange medium flowing in the heat exchange medium channel 43. The heat exchange medium includes air, water, or supercritical carbon dioxide.

[0066] Specifically, in this embodiment, the cold and hot heat storage media are solid heat storage particles, and a fluidized bed heat exchanger can be used as the external heat exchange device 40. The fluidized bed heat exchanger is further selected as an external bubbling fluidized bed heat exchanger, which can more flexibly adjust the temperature inside the bed and the corresponding output temperature of the heat exchange medium, which is beneficial to the large-scale design of the external heat exchange device 40.

[0067] The air chamber 45 is configured to receive a fluidizing gas, typically air, but other suitable fluid forms may be selected depending on the specific circumstances. After entering the air chamber 45, the fluidizing gas passes upwards through the air distribution plate 46 and enters the main chamber 44, causing the hot thermal storage medium (such as high-temperature solid thermal storage particles) within the main chamber 44 to enter a dynamic fluidized state. In this fluidized state, the hot thermal storage medium (such as high-temperature solid thermal storage particles) achieves dense contact, and efficient and relatively uniform heat transfer is achieved through the agitation of the fluidizing gas. This fluidized heat exchange method improves the overall heat exchange efficiency and makes the heat flux distribution and temperature field inside the fluidized bed heat exchanger more uniform, effectively reducing the occurrence of overheating or undercooling in localized areas.

[0068] The heat exchange medium channel 43 is located above the air distribution plate 46 and is used to introduce a heat exchange medium with good thermal conductivity. The heat exchange medium includes air, water, or supercritical carbon dioxide; the specific choice depends on the actual heat exchange power requirements of the system. The hot thermal storage medium (such as high-temperature solid thermal storage particles) in a fluidized state exchanges heat fully with the heat exchange medium flowing in the heat exchange medium channel 43, releasing the high-temperature heat stored within it to the heat exchange medium. The heat exchange medium heated by the heat exchange medium channel 43 is then drawn out for external use. The hot thermal storage medium (such as high-temperature solid thermal storage particles), after releasing heat and cooling down in the fluidized bed heat exchanger, is transformed back into a cold thermal storage medium (such as low-temperature solid thermal storage particles) so that it can be transported back and participate in the heat extraction cycle again.

[0069] Furthermore, when thermochemical thermal storage particles are selected as the solid thermal storage particles, the bubbling fluidized bed form can promote sufficient contact between the particles and the fluidizing gas because a gas-solidification chemical reaction needs to occur during heat release. Inside the fluidized bed heat exchanger, the thermochemical thermal storage particles not only release sensible heat and chemical heat to the heat exchange medium, but also undergo chemical reactions to be re-converted into decomposable compounds. This allows the cooled thermochemical thermal storage particles to regain their endothermic decomposition ability, ensuring that after being transported back to the first storage device 10, they can re-enter the furnace of the boiler 200 for a new round of heat extraction and thermochemical reaction, thereby ensuring the heat storage and release cycle of the entire furnace heat extraction system.

[0070] In this embodiment, to further improve the internal heat exchange flow field, the fluidized bed heat exchanger is also equipped with a wind cap and a baffle plate 47. The wind cap is arranged above the air distribution plate 46 to evenly distribute the fluidizing gas in the air chamber 45 into the main chamber 44 and prevent the heat storage medium above from perforating and flowing back. The baffle plate 47 is disposed inside the main chamber 44 to guide the flow path of the hot heat storage medium in the main chamber 44, extending its residence time and heat exchange stroke.

[0071] It is understood that the use of a fluidized bed heat exchanger (such as an external bubbling fluidized bed heat exchanger) as the external heat exchange device 40 in this embodiment is only a specific preferred embodiment. In practical applications, the specific structure and type of the external heat exchange device 40 are not limited to this.

[0072] As an example, for the solid heat storage particles of this embodiment, in addition to the bubbling fluidized bed heat exchanger mentioned above, the external heat exchange device 40 can also be a circulating fluidized bed heat exchanger, a moving bed heat exchanger (such as a shell and tube moving bed heat exchanger), a fixed bed heat exchanger, or a dense flow particle heat exchanger, or other forms of heat exchange equipment that can achieve efficient heat transfer of gas-solid two-phase flow or particle flow.

[0073] In this embodiment, both the first storage device 10 and the second storage device 30 are conical-bottom silos with thermal insulation jackets. Specifically, the first storage device 10 and the second storage device 30 are made of high-temperature resistant alloy material and are in the form of conical-bottom silos, which can form a cone-shaped structure that is wider at the top and narrower at the bottom. The heat storage medium stored inside can flow out by gravity, achieving effective air evacuation.

[0074] Meanwhile, both the first storage device 10 and the second storage device 30 have outer walls and inner walls, with insulation material filling the space between them, thus forming an insulation interlayer. This insulation interlayer design can reduce heat loss of the heat storage medium during storage and maintain the overall heat storage effect.

[0075] In this embodiment, the second storage device 30 is detachably connected between the in-furnace heat absorption device 20 and the external heat exchange device 40. Specifically, the second storage device 30, used to store the hot thermal storage medium, has a detachable structure and is detachably connected between the heat absorption discharge end of the in-furnace heat absorption device 20 and the heat exchange feed end 41 of the external heat exchange device 40. Through this detachable design, after collecting and storing the hot thermal storage medium, the second storage device 30 can be moved and loaded onto trucks or other transport vehicles for loading and transportation over a certain distance. This allows the user side at the remote location to complete the heat release process by simply arranging the external heat exchange device 40 and the first storage device 10 to receive the cold thermal storage medium, improving the flexibility of cross-regional heat energy distribution and scheduling. Simultaneously, the cold thermal storage medium collected after heat release at the remote location can also be transported back to the first storage device 10 on the boiler 200 side by a transport vehicle, forming a cross-regional heat storage and release cycle.

[0076] Furthermore, as an example of a detachable structure for the second storage device 30, when implementing a detachable connection, each interface of the second storage device 30 can be configured with a flange connection structure or a quick-release locking assembly, and can be connected with the corresponding ports of the furnace heat absorption device 20 and the furnace heat exchange device 40 using high-temperature resistant sealing joints, so as to quickly disconnect the connection and carry out hoisting and movement after collecting and storing the hot heat storage medium.

[0077] Understandably, the specific mechanical structure, docking method, and sealing form for the detachable connection of the second storage device 30 in this embodiment can be designed according to the actual industrial transportation needs and on-site loading and unloading conditions, and are not specifically limited here.

[0078] In this embodiment, the solid thermal storage particles are sensible thermal storage particles or thermochemical thermal storage particles.

[0079] Sensible heat storage particles include natural sand, quartz sand, alumina, or ceramics. Specifically, when sensible heat storage particles are selected as solid heat storage particles, they can be in the form of natural sand, quartz sand, alumina, or ceramics. These particles have good physical stability and high-temperature resistance. When passing through the heat absorption device 20 in the furnace, they absorb and store the high-temperature waste heat from the furnace of boiler 200 by relying on their own temperature rise. No chemical reaction occurs during the entire heat absorption and release process, making operation and control simple and suitable for conventional heat extraction and storage scenarios where the chemical stability of the medium is high.

[0080] Thermochemical thermal storage particles include non-redox thermochemical particles and redox thermochemical particles. Redox thermochemical particles are metal oxides that can generate oxygen-rich gas upon heat absorption. When thermochemical thermal storage particles are selected for solid thermal storage, they can be further divided into non-redox thermochemical particles and redox thermochemical particles. These types of thermochemical thermal storage particles not only undergo temperature changes during heat absorption but also involve endothermic chemical reactions, converting the thermal energy of the boiler's 200°C furnace into chemical energy for storage. This results in high energy density and effectively reduces the volume requirements of the storage device.

[0081] Non-redox thermochemical particles include materials such as calcium carbonate. Redox thermochemical particles include manganese oxide or copper oxide. Specifically, redox thermochemical particles can be metal oxides that can generate oxygen-enriched gas when absorbing heat at high temperatures, specifically including manganese oxide or copper oxide particles. When the above-mentioned metal oxides are used as the heat storage medium, they undergo thermal decomposition reactions in the high-temperature environment of the furnace and absorb a large amount of heat energy. At the same time, the oxygen-enriched gas generated by this reaction decomposition can be collected and used for oxygen-enriched combustion in boiler 200, thereby further improving the combustion efficiency of fuel in boiler 200. By selecting different solid heat storage particles, the boiler furnace heat extraction system 100 of this embodiment can flexibly adapt to different boiler 200 temperature parameters and target operating conditions.

[0082] The boiler furnace heat extraction system 100 of this embodiment also includes a gas-solid separation device (not shown in the figure) and a combustion-supporting flow guide pipe (not shown in the figure).

[0083] The gas-solid separation device is located between the heat absorption and discharge end of the furnace heat absorption device 20 and the second storage device 30, and has a gas outlet. The combustion-supporting guide pipe is located between the gas outlet of the gas-solid separation device and the furnace of the boiler 200; the thermochemical heat storage particles are oxidation-reduction thermochemical particles.

[0084] The gas-solid separation device is configured to separate the oxygen-enriched gas generated when the thermochemical thermal storage particles absorb heat from the solid thermochemical thermal storage particles. The combustion-supporting guide pipe is configured to introduce the separated oxygen-enriched gas into the furnace of boiler 200 to assist the boiler 200 furnace in oxygen-enriched combustion.

[0085] Specifically, when redox thermochemical particles are used as the heat storage medium, these particles flow through the furnace heat absorption device 20 in the high-temperature environment of the boiler 200 furnace. In addition to absorbing sensible heat and causing their own temperature to rise, they also undergo a thermal decomposition chemical reaction. During this chemical reaction, the redox thermochemical particles convert thermal energy into chemical energy for storage, and generate a large amount of oxygen-enriched gas along with the reaction decomposition.

[0086] To effectively recover and utilize the generated oxygen-enriched gas, a gas-solid separation device can be added between the heat absorption outlet of the furnace heat absorption device 20 and the main pipeline of the second storage device 30. The substance flowing out of the furnace heat absorption device 20 is a gas-solid mixture containing decomposed solid thermochemical heat storage particles and oxygen-enriched gas. After entering the gas-solid separation device, the gas-solid separation device separates the oxygen-enriched gas from the solid thermochemical heat storage particles. The separated solid thermochemical heat storage particles continue to flow under gravity and enter the second storage device 30 below for storage, while the separated oxygen-enriched gas is discharged from the gas outlet of the gas-solid separation device.

[0087] Furthermore, the combustion-supporting guide pipe connects the gas outlet of the gas-solid separation device to the air inlet side or burner area of ​​the boiler 200 furnace. The oxygen-rich gas collected from the gas outlet is returned to the boiler 200 furnace via the combustion-supporting guide pipe. Because this gas is rich in oxygen, its introduction into the furnace as a combustion-supporting gas to participate in the fuel combustion reaction improves the combustion conditions within the furnace, achieving oxygen-rich combustion in the boiler 200. This also allows for the recovery and utilization of byproducts from the reaction process, significantly improving the combustion efficiency of the boiler 200 fuel and enhancing the overall economy and operational performance of the boiler unit.

[0088] In this embodiment, the gas-solid separation device can be a high-temperature cyclone separator, a gravity settling chamber, or a ceramic filter, or other separation equipment suitable for high-temperature operating conditions. As an example, a high-temperature cyclone separator can be used, with its side tangentially connected to the heat absorption discharge end of the furnace heat absorption device 20, its top serving as the gas outlet, and its bottom connected to the second storage device 30. After the gas-solid mixture enters the high-temperature cyclone separator, under the action of centrifugal force, the larger solid thermochemical heat storage particles are separated and rotate down along the wall to the bottom to enter the second storage device 30 for storage, while the lighter oxygen-enriched gas gathers towards the center and is discharged upward from the gas outlet, and is correspondingly guided back into the furnace of the boiler 200 through the combustion-supporting guide pipe.

[0089] Understandably, the gas-solid separation device and the combustion-supporting guide pipe in this embodiment can be specifically configured according to the actual working conditions. It is only necessary to separate the oxygen-enriched gas generated when the thermochemical heat storage particles absorb heat from the solid thermochemical heat storage particles, and introduce the separated oxygen-enriched gas into the furnace of the boiler 200 to assist the boiler 200 furnace in oxygen-enriched combustion. No specific limitations are made here.

[0090] The specific working process of the boiler furnace heat extraction system 100 in this embodiment is as follows: The cold thermal storage medium in the first storage device 10 flows by gravity through the first discharge valve 14 into the furnace heat absorption device 20 inside the boiler 200, absorbing heat from the high-temperature flue gas in the furnace and converting it into a hot thermal storage medium. If redox thermochemical particles are used, a thermal decomposition reaction will occur during heat absorption to produce oxygen-enriched gas. Subsequently, the outflowing gas-solid mixture enters the gas-solid separation device, and the separated oxygen-enriched gas is led back into the furnace through the combustion-supporting guide pipe to assist combustion, while the solid hot thermal storage medium continues to flow by gravity into the second storage device 30 for temporary storage through the second feed valve 33. For remote heating scenarios, the heat can be transferred and transported externally through the detachable structure of the second storage device 30.

[0091] When there is an external heat demand, the second discharge valve 34 at the bottom of the second storage device 30 is opened, and the hot thermal storage medium flows by gravity into the furnace external heat exchange device 40 (such as a fluidized bed heat exchanger) below. Under the action of fluidizing gas, the thermal storage medium in a fluidized state exchanges heat with the heat exchange medium in the heat exchange medium channel 43. The heat exchange medium after absorbing heat is led out for external use (such as for heating in industrial parks, directly entering the superheater or reheater of steam turbine units for power generation, or for heating during peak electricity demand periods to improve the peak capacity of boiler units, etc.). The hot thermal storage medium that has completed the heat release and cooling process is transformed back into a cold thermal storage medium and discharged into the conveying device 50. Subsequently, the conveying device 50 provides upward power to lift the returned cold thermal storage medium to the first storage device 10 located at a higher position, thereby completing the overall circulation of the thermal storage medium.

[0092] In addition, when the furnace heat absorption device 20 is shut down, the wall temperature measuring thermocouple located at the bottom will monitor the pipe wall temperature in real time. If the monitored temperature is higher than the preset safe temperature, the purging and cooling assembly will be activated to purge and unblock the furnace heat absorption device 20 and cool it down by introducing airflow, so as to prevent the pipe from dry burning failure in the high-temperature furnace and ensure operational safety.

[0093] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A boiler furnace heat extraction system, characterized by, include: The first storage device is configured to store the cold heat storage medium to be absorbed. The furnace heat absorption device is installed inside the boiler furnace and has a heat absorption feed end and a heat absorption discharge end. The heat absorption feed end is connected to the first storage device to allow the cold heat storage medium to circulate and absorb the heat inside the boiler furnace. The second storage device is connected to the heat absorption discharge end and is configured to receive and store the hot heat storage medium formed after the heat absorption device in the furnace absorbs heat. An external heat exchange device is installed outside the boiler furnace and has a heat exchange feed end, a heat exchange discharge end, and a heat exchange medium channel installed inside. The heat exchange feed end is connected to the second storage device to receive the hot storage medium and exchange heat with the heat exchange medium entering the heat exchange medium channel. A conveying device, connected between the heat exchange outlet and the first storage device, is configured to convey the cold-state heat storage medium formed after heat exchange back to the first storage device. The cold-state heat storage medium and the hot-state heat storage medium are solid heat storage particles; the first storage device, the in-furnace heat absorption device, the second storage device, and the external heat exchange device are arranged sequentially from high to low along the direction of gravity.

2. The boiler furnace heat extraction system according to claim 1, characterized in that, The location of the in-furnace heat absorption device inside the boiler furnace is determined according to the temperature field distribution inside the boiler furnace and matches the heat storage temperature zone of the cold heat storage medium.

3. The boiler furnace heat extraction system according to claim 1, characterized in that, The first storage device is provided with a first inlet and a first outlet, and the first storage device is connected to the heat-absorbing inlet of the furnace heat-absorbing device through the first outlet; The second storage device is provided with a second inlet and a second outlet. The second storage device is connected to the heat absorption outlet of the furnace heat absorption device through the second inlet and to the heat exchange inlet of the furnace heat exchange device through the second outlet. The feed side of the conveying device is connected to the heat exchange discharge end of the furnace heat exchange device, and the discharge side of the conveying device is connected to the first feed inlet of the first storage device.

4. The boiler furnace heat extraction system of claim 3, wherein, Also includes: The first feed valve is located at the first feed inlet of the first storage device and is used to adjust the feed flow rate of the cold heat storage medium. The first discharge valve is located at the first discharge port of the first storage device and is used to adjust the discharge flow rate of the cold heat storage medium. The second feed valve is located at the second feed inlet of the second storage device and is used to adjust the feed flow rate of the hot storage medium. The second discharge valve is located at the second discharge port of the second storage device and is used to adjust the discharge flow rate of the hot storage medium. The first feed valve, the first discharge valve, the second feed valve, and the second discharge valve all have a heat insulation layer or a cooling protection structure.

5. The boiler furnace heat extraction system of claim 1, wherein, Also includes: The purging and cooling assembly is at least connected to the interior of the furnace heat absorption device and is configured to purge and cool the furnace heat absorption device by introducing airflow when the furnace heat absorption device stops working.

6. The boiler furnace heat extraction system according to claim 1, characterized in that, The furnace heat absorption device includes straight tubes, serpentine tubes, coils, or multiple parallel tube bundles; The materials used for the furnace heat absorption device include high-temperature resistant alloy tubes, ceramic-lined metal tubes, or composite wear-resistant tubes.

7. The boiler furnace heat extraction system according to claim 1, characterized in that, The external heat exchange device is a fluidized bed heat exchanger, which includes at least a main chamber, an air chamber located at the bottom of the main chamber, an air distribution plate located at the top of the air chamber, and a heat exchange medium channel located above the air distribution plate. The air chamber is configured to receive fluidizing gas, which passes upward through the air distribution plate to fluidize the hot storage medium and exchange heat with the heat exchange medium flowing in the heat exchange medium channel. The heat exchange medium includes air, water, or supercritical carbon dioxide.

8. The boiler furnace heat extraction system according to claim 1, characterized in that, Both the first storage device and the second storage device are conical-bottom silos with thermal insulation jackets; The second storage device is detachably connected between the in-furnace heat absorption device and the out-of-furnace heat exchange device.

9. The boiler furnace heat extraction system according to claim 1, characterized in that, The solid thermal storage particles are sensible thermal storage particles or thermochemical thermal storage particles. The sensible heat storage particles include natural sand, quartz sand, alumina, or ceramics. The thermochemical heat storage particles include non-redox thermochemical particles or redox thermochemical particles, wherein the redox thermochemical particles are metal oxides that can generate oxygen-rich gas when absorbing heat. The non-redox thermochemical particles include calcium carbonate; the redox thermochemical particles include manganese oxide or copper oxide.

10. The boiler furnace heat extraction system of claim 9, wherein, Also includes: A gas-solid separation device is installed between the heat absorption discharge end of the furnace heat absorption device and the second storage device, and has a gas discharge port; A combustion-supporting flow guide pipe is installed between the gas outlet of the gas-solid separation device and the boiler furnace. The thermochemical heat storage particles are redox thermochemical particles. The gas-solid separation device is configured to separate the oxygen-enriched gas generated when the thermochemical thermal storage particles absorb heat from the solid thermochemical thermal storage particles, and the combustion-supporting guide pipe is configured to introduce the separated oxygen-enriched gas into the boiler furnace to assist the boiler furnace in oxygen-enriched combustion.

Images